Knife sheath



FIG. 1 is a perspective view of a knife sheath incorporating my novel design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a side elevational view thereof;

FIG. 5 is the opposite side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof. 

The ornamental design for a knife sheath, as shown and described. 